In the field of an automobile, a typical example of vehicle, an audio apparatus has come into widespread use in recent years allowing passengers to enjoy various contents such as music in a vehicle.
In such a conventional audio apparatus, a passenger inserts a portable music storage medium such as a CD (compact disk), MD (mini-disk), cassette tape into the audio apparatus and enjoys music of his/her choice by replaying/outputting it from data stored in the music storage medium.
However, an audio apparatus using such a music storage medium is burdensome because the passenger needs to take the storage medium storing music to be replayed in the vehicle into the vehicle every time the passenger gets on the vehicle.
Thus, the Japanese Patent Laid-Open No. 11-30986, etc. proposes a technology for directly receiving digitized music data from the outside through an audio apparatus using a music distribution service and enjoying the music data in the vehicle without using a music recording medium.
Here, the technology described in the Japanese Patent Laid-Open No. 11-30986 will be summarized below.
The vehicle music data acquisition system described in this Publication consists of an information center that distributes music to vehicles and a vehicle capable of wirelessly communicating with the information center (see FIG. 2 of the relevant Publication) and the music distribution procedure in such a system configuration is explained with reference to FIG. 2 of the relevant Publication.
That is, the vehicle sends data about a music replaying condition in the own vehicle (including information to identify music of a distribution request) to the information center.
Upon reception of the data about the music replaying condition, the information center determines whether the requested music data exists in the information center or not and if the music data does not exist, the information center acquires the data on the Internet from the outside. Then, the information center creates music data with the amount of data reduced (compressed) based on the data about the music replaying condition and sends the music data created to the vehicle. The vehicle replays the music based on the received music data.
According to the audio apparatus using this music distribution service, the passenger can enjoy any music at any time without the need to prepare any music storage medium. This allows the passenger to easily enjoy music of his/her choice in the vehicle, providing an effect of allowing the passenger to spend his/her time comfortably in the vehicle.
Furthermore, the technology described in the Japanese Patent Laid-Open No. 10-240207 will be summarized below.
This Publication describes a touch-screen type audio-visual replay digital system and a plurality of windows appearing on a display shows information on audio-visual contents that can be replayed.
The user can select a desired window from among a plurality of windows displayed to easily replay the audio-visual contents requested to be replayed.
On the other hand, recently, with the development of the Internet, music distribution services indirectly using the Internet are provided as described below, which allows the user to download digitized contents data such as music to an information storage medium such as a memory card and enjoy music of his/her choice easily.
Furthermore, recently, individuals often carry with them portable audio apparatuses and these portable audio apparatuses are also making it easier to enjoy music using music data stored in an information storage medium.
By the way, people go for a long-distance drive on a trip, etc., a plurality of passengers often gets on the vehicle, in which case, because preference of music varies from one person to another, it is preferred that these passengers be able to enjoy music of their respective choices and spend their time during the long-distance drive comfortably.
In a vehicle equipped with an audio apparatus using a conventional music storage medium, satisfying such as demand requires each passenger to record music of his/her choice to a music storage medium corresponding to the audio apparatus or purchase one and take the music storage medium into the vehicle.
As in the case of the Japanese Patent Laid-Open No. 11-30986, the audio apparatus using the music distribution service provided from the information center can freely obtain a variety of music data at any time by a required amount. This allows the passengers to freely enjoy music of their choice without the need to take the music storage medium into the vehicle.
The audio apparatus using the music distribution service provides such convenience, but on the other hand, because this audio apparatus receives music data from the outside by radio (wireless telephone line, etc.), it takes some time of communication to download music data of one piece of music for example. Therefore, if, for example, electromagnetic interference occurs while the music data is being downloaded during a drive, the audio apparatus is unable to reliably receive the music data of the relevant piece of music.
And in the case where the music data cannot be received reliably, it is necessary to receive the music data again. Thus, even the audio apparatus using the music distribution service is still not sufficient in respect of user friendliness.
Moreover, downloading music data from the music distribution service in the current communication environment entails a high communication cost, and so it is problematic in respect of cost, too.
Therefore, one possible method of enjoying music of one's choice reliably and at low cost without using such a music distribution service is to use music data included in a portable audio apparatus. This is because the portable audio apparatus that each passenger carries includes music data of his/her choice beforehand and using this music data allows the passenger to reliably enjoy music data of his/her choice in the vehicle.
However, the shape and mode of a portable audio apparatus varies from one model to another, and the wired connection port and the shape of its information storage medium also vary. For this reason, using this portable audio apparatus in the vehicle requires the passenger to set the audio apparatus in a mount pre-installed in the vehicle, connect it to an in-car audio apparatus via a cable or insert or remove the information storage medium to take the music data of portable audio apparatuses of all models into the in-car audio apparatus, which is difficult in practice.
Moreover, even if wired connection ports of portable audio apparatuses of all models and information storage media are standardized having a common shape and mode, there remains a possibility that the passenger will still need to set the audio apparatus in the mount and insert or remove the information storage media, which is a problem of requiring time and trouble.
Moreover, the conventional audio system above generally comprises a main unit that controls reproduction of musical pieces (contents) connected to a plurality of speakers via cables. Therefore, when an audio system is also mounted when the vehicle is purchased or when a desired audio system is mounted later, it is troublesome to lay cables for the audio system in a limited space of the vehicle.
Furthermore, also in the car cabin design stage, the degree of freedom in design may be reduced because it is necessary to consider locations of cables for the audio system and operability for cabling, etc.
Furthermore, in a conventional audio system, once a determined system configuration has been incorporated in the vehicle, subsequent changes to the system configuration are not easy. Thus, when the user wants to replay a CD (compact disk) in the main unit that is provided with only functions of a radio tuner and cassette tape recorder, a widespread method for meeting such a demand is to carry into the vehicle a portable CD player, a transmitter that FM-modulates an output signal and allows a radio tuner on the audio system side to receive the output signal or an adapter that reads the output signal of the CD player through the head of the cassette tape recorder and thereby indirectly reproduces the output signal of the CD player through the audio system.
However, the above indirect reproduction method requires that a portable CD player and FM transmitter, etc. be carried into the vehicle and their locations be secured in a narrow car cabin, and restricts the original seating space for passengers, provides not good looking and also has a problem with the quality of musical pieces.